refactor: unify channel plugin resolution, family ordering, and changelog entry tooling

test/scripts/changelog-add.test.ts

@@ -0,0 +1,45 @@
+import { describe, expect, it } from "vitest";
+import { insertUnreleasedChangelogEntry } from "../../scripts/changelog-add.ts";
+
+const SAMPLE = `# Changelog
+
+## 2026.2.24 (Unreleased)
+
+### Changes
+
+- Existing change.
+
+### Fixes
+
+- Existing fix.
+
+## 2026.2.23
+
+### Changes
+
+- Older entry.
+`;
+
+describe("changelog-add", () => {
+  it("inserts a new unreleased fixes entry before the next version section", () => {
+    const next = insertUnreleasedChangelogEntry(
+      SAMPLE,
+      "fixes",
+      "New fix entry. (#123) Thanks @someone.",
+    );
+    expect(next).toContain(
+      "- Existing fix.\n- New fix entry. (#123) Thanks @someone.\n\n## 2026.2.23",
+    );
+  });
+
+  it("normalizes missing bullet prefix", () => {
+    const next = insertUnreleasedChangelogEntry(SAMPLE, "changes", "New change.");
+    expect(next).toContain("- Existing change.\n- New change.\n\n### Fixes");
+  });
+
+  it("does not duplicate identical entry", () => {
+    const once = insertUnreleasedChangelogEntry(SAMPLE, "fixes", "New fix.");
+    const twice = insertUnreleasedChangelogEntry(once, "fixes", "New fix.");
+    expect(twice).toBe(once);
+  });
+});